Bleach vs pucks effective chlorine.......

[chrisexv6]

Wife currently insists the pool looks "10x better" using pucks than bleach (in our case, it only looks better because recently I got lazy putting bleach in the pool, along with being sidetracked on a billion other projects).

Trying to get the exact numbers to compare the effective chlorine amount of 6% bleach vs. the cal hypo pucks she bought at the pool store. Sure enough bleach is cheaper (we've gone thru 75% of a $22.00 jug of pucks in 1.5 weeks), but Id like to show her other numbers that explain why bleach is just as good a source of chlorine (except for the fact that you need to keep pouring it everyday).

I know someone here had this math done, but I cannot find the post using Search.

Thanks!
-Chris

[CarlD]

It's really simple. Use pucks long enough and your CYA (Stabilizer) level will rise so high that you WILL get algae growth--unless you know how to compensate.

Pucks will also drive your pH down so you will always be counter-acting acidity.

Bleach does neither. Bleach adds a little tiny bit of salt to your water, but that just makes it feel softer. It's much easier to calculate how much bleach you need vs how many pucks.

As for the chlorination: there is NO difference once the chlorine hits the water. None, Nada, Gornischt, Rien.

[chrisexv6]

Oh trust me, I dont need to be told the advantages of bleach :) my wife is just a non-believer because the pool looks clearer with the pucks (like I said, that only happened because I wasnt keeping up with my bleach). I was actually thinking about getting the Liquidator, which would be the equivalent of our puck cholorinator anyway.

Sometimes the only thing that gets her attention is $$$ :) 22.00 in bleach gets me almost a month worth of bleach vs 22.00 of pucks lasting about 10 days.

I was just wondering if there is a quantitative way to say 1 puck (at say 45% effective chlorine) = x oz of 6% bleach. That way I could say 1 tub of pucks = y gallons of bleach, then compare cost directly.

-Chris

[mbar]

I'm not sure of the math of bleach vs pucks, but I do know that cal-hypo pucks are also adding calcium to your water. The only way to get rid of excess calcium is to do a partial drain and refill. Everything you put in your pool adds something, but the olnly thing bleach adds is sodium - which is good for the eyes! It is also almost ph neutral. Once you get your cya in a range, it is very easy to figure out your own pool chlorine demands. You will be able to adjust easily for excess bather loads. It is easier to pour 1/2 bottle of bleach in when you need a little extra;) I know that you are a bleach fan, but tell your wife not only is it cheaper, but you can use it for other things around the house too, so it will never go to waste:)

[nisqu]

I think what Chris needs to know is what is the effect if one gallon of 6% bleach on say 10000 gals of water, I too have searched for this info.
It's the only way to compare the cost of bleach VS pucks.

[chem geek]

I did a cost comparison of chlorine sources in this thread (http://www.poolforum.com/pf2/showthread.php?t=6991). Basically, Trichlor at first appears to be less expensive per chlorine added until you account for the cost of the chemical needed to adjust the pH since Trichlor is very acidic. Obviously the costs are examples and you may find your costs to be somewhat different, especially for bleach and chlorinating liquid. The thing to keep in mind is that Dichlor and Trichlor will add to Cyanuric Acid (CYA) while Cal-Hypo will add to Calcium Hardness (CH).

The size of Trichlor pucks varies, but an 8-ounce puck in a 10,000 gallon pool will increase FC by 5.5 ppm and CYA by 3.3 ppm. It takes 14 cups of 6% bleach to get the same FC or 7 cups of 12.5% chlorinating liquid. It would take 11 ounces weight of Cal-Hypo 65% to get the same FC.